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Full-Text Articles in Physical Sciences and Mathematics

Comparing Commonly Used Aquatic Habitat Modeling Methods For Native Fishes, Eryn K. Turney Aug 2023

Comparing Commonly Used Aquatic Habitat Modeling Methods For Native Fishes, Eryn K. Turney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water resources are managed for a variety of human needs, including agriculture, industrial and municipal consumption, hydropower generation, and recreation. There has been a recent push to incorporate habitat needs of aquatic wildlife into water management models alongside these other uses, particularly as competition for limited water resources in a changing climate has reduced instream flow and contributed to declining native fish populations. Habitat models are used to estimate species distributions and differentiate between suitable and unsuitable habitat based on variables important to a given species, but are not usually incorporated into water management models. Because there are many ways …


Influence Of Hydrologic History On Nitrogen Cycling In Lake Sediments, Emily Jainarain Aug 2023

Influence Of Hydrologic History On Nitrogen Cycling In Lake Sediments, Emily Jainarain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water quality is declining in freshwater lakes around the world due to environmental change and anthropogenic activities that threaten the physical, ecological, and geochemical integrity of freshwater ecosystems. Excess N and P in lakes can cause eutrophication, a major driver of water quality impairment that leads to excessive algal growth, or harmful algal blooms (HABs), and poses risks to recreation, fisheries, and public drinking water. Water level fluctuations in lakes are expected to become more frequent and intense as climate change increases periods of drought and alters precipitation patterns, and fluctuations may stimulate biogeochemical reactions in littoral sediments that add …


Overcoming Barriers To Aquatic Plant Restoration: Addressing Gaps In Species Identification And Planting Techniques In The Intermountain West, Kate A. Sinnott Aug 2023

Overcoming Barriers To Aquatic Plant Restoration: Addressing Gaps In Species Identification And Planting Techniques In The Intermountain West, Kate A. Sinnott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aquatic ecosystems provide many critical and economically valuable benefits, including drinking water, food, recreational opportunities, and water supply for irrigation and agriculture. However, the health of these systems has been severely impacted by human activities such as pollution, land conversion, and introductions of harmful species. Restoring native aquatic plants can help reverse this damage and reestablish benefits, though it is not a common practice. With an objective to increase capacity for aquatic plant restoration in the Intermountain West, I identified and addressed two major barriers: 1) a lack of confidence in aquatic species identification among wetland professionals, and 2) underdeveloped …


Big Fish And More Of Them: Salmonid Habitat Availability, Quality, And Use Across Multiple Scales Within A River-Reservoir System, John S. Mclaren V Aug 2023

Big Fish And More Of Them: Salmonid Habitat Availability, Quality, And Use Across Multiple Scales Within A River-Reservoir System, John S. Mclaren V

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Reservoirs and their associated rivers provide water for agricultural and municipal uses, ecological benefits for fish and wildlife, and associated recreational activity. However, in the Greater Yellowstone Ecosystem climate change and population growth are putting pressure on water quality and supply, potentially damaging the unique and economically important coldwater trout habitat that these systems support. In this study, the author investigates the impact of changing water quality and supply on trout habitat quality, quantity, and selection to assist conservation goals in the Henry’s Fork Watershed in eastern Idaho. The study found that higher availability of cold-water refuge habitat in Island …


Effects Of Soil Amendments On Water Quality And Hydrologic Properties In Low Impact Development Systems, Lily Wetterlin Aug 2023

Effects Of Soil Amendments On Water Quality And Hydrologic Properties In Low Impact Development Systems, Lily Wetterlin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Low impact development (LID) systems are practices that use natural elements, such as soils and vegetation, to absorb and filter stormwater to protect water quality and aquatic habitats. Many LID designs use native soils; however, urban soils typically have a limited potential for infiltrating and treating stormwater. Incorporation of soil amendments, such as compost and biochar, into LID soils can improve the physical properties of soil. However, soil amendments may increase or decrease pollutants in the water leaving the site. A comparison of the effects of different types and application rates of amendments on water quality is necessary to determine …


Getting The Dirt On Phosphorus Pollution In Mountain Lakes: Are Rising Soil Temperatures Contributing To Eutrophication In Mountain Watersheds?, Gordon O. Gianniny May 2023

Getting The Dirt On Phosphorus Pollution In Mountain Lakes: Are Rising Soil Temperatures Contributing To Eutrophication In Mountain Watersheds?, Gordon O. Gianniny

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mountain watersheds provide a critical supply of clean water to millions of people around the world. In recent years, evidence of a concerning trend has emerged in these watersheds: rising phosphorus (P) concentrations. P often acts as the limiting nutrient in mountain lake ecosystems, so increasing P availability in mountain lakes and streams has the potential to drastically increase algal growth in these systems. In extreme cases, increasing mountain lake P concentrations may even cause harmful algal blooms that degrade downstream water quality. While the implications of rising P concentrations in mountain lakes are serious, the cause driving this widespread …


Valley Bottom Inundation Patterns In Beaver-Modified Streams: A Potential Proxy For Hydrologic Inefficiency, Karen Bartelt Dec 2021

Valley Bottom Inundation Patterns In Beaver-Modified Streams: A Potential Proxy For Hydrologic Inefficiency, Karen Bartelt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For centuries river management and land use actions in North America have caused widespread stream degradation where water now flows downstream with artificially high efficiency. When present, beaver dams slow the flow of water and decrease the efficiency of water conveyance through the landscape. These effects are often to the benefit of the function of natural physical processes and ecology of the stream. The benefits provided by beaver dams have been well studied at small scales, but the methods that these studies rely on are often expensive and time consuming and consequently not feasible to deploy at larger spatial scales …


Predictive Models Of Post-Wildfire Debris Flow Volume And Grain Size Distribution In The Intermountain West, Sara Wall Dec 2021

Predictive Models Of Post-Wildfire Debris Flow Volume And Grain Size Distribution In The Intermountain West, Sara Wall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Post-fire debris flows represent the most erosive and potentially hazardous consequence associated with increasing wildfire severity. While an abundance of research has explored where they are likely to occur and their potential magnitude, investigations into understanding how they impact downstream resources are limited. Recent advancements are seeking to link predictive models together to be able to predict how erosion after wildfire may impact reservoirs and aquatic habitat downstream. However, there are two key missing pieces into our ability to examine watershed-scale impacts of post-fire erosion. These include having accurate predictions of how much sediment is likely to be deposited by …


Essays Related To Water Transfer And Water Sharing: The Past And The Present, Arpita Nehra Dec 2021

Essays Related To Water Transfer And Water Sharing: The Past And The Present, Arpita Nehra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation explores the impacts of resource procurement on economic growth and urbanization in a county through a historical case study, moving on to discuss the welfare impacts of resource-sharing in two regions. The first two essays explore the impact of the Owens Valley water transfer in the 1900s on the urban sprawl and the economic growth of Los Angeles. The main contribution that the first two essays make is to present an empirical analysis on the impact of procurement of resources on the economy. The third essay examines the welfare impacts of a proposed water sharing and development project. …


Water, Fish, And Fire: Interdisciplinary Research On Ecosystem Services And Climate Adaptation, Liana Prudencio Dec 2020

Water, Fish, And Fire: Interdisciplinary Research On Ecosystem Services And Climate Adaptation, Liana Prudencio

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ecosystem services, or benefits from the environment, are plentiful and vary from place to place. Human activities and climate change have impacted these services in every region of the world. This dissertation explores multiple ecosystem services, from water quality improvement to provisioning of fish and habitat, in multiple and international contexts. The first chapter synthesizes the literature on stormwater management and ecosystem services, finding that research at this intersection has provided many parcel-level studies and frameworks for implementing green infrastructure. The second chapter extends the stormwater management literature by quantifying the impacts of green infrastructure on water quantity and quality …


Environmental Controls On Didymosphenia Geminata Bloom Formation, Lindsay Capito Dec 2020

Environmental Controls On Didymosphenia Geminata Bloom Formation, Lindsay Capito

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Climate change is causing rapid glacial recession and earlier snowmelt, which alter the physical and chemical properties of rivers. As a result, organisms at the base of the food web are responding in unforeseen ways. We use the nuisance algae D. geminata (Didymo) as a case study for how climate induced shifts in the timing of glacial and snowmelt runoff are affecting river ecosystems. We evaluated how shifts in the timing of nutrient concentrations and light availability affect nuisance blooms of Didymo in three complementary ways. These are, field studies across streams in various stages of glacial recession, weekly measurements …


Greening-Induced Runoff Loss In The Western United States, Xueyan Zhang Aug 2020

Greening-Induced Runoff Loss In The Western United States, Xueyan Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study assessed how vegetation will influence long-term runoff trends across the western United States (western US) in the future. I used a land surface model with improved dynamic vegetation root processes to better quantify regional runoff trends across five regions (Upper and Lower Colorado, Great Basin, Pacific Northwest, and California). The model was driven by statistically downscaled and bias-corrected outputs from three global climate models under the Representative Concentration Pathway 4.5 and 8.5 scenarios. Vegetation greening dominated significant transpiration increases that contributed most to increasing evapotranspiration across the western US, especially during spring and summer. Consistent with these trends, …


Evaluation Of Best Practices For Urban Water Conservation And Water-Smart Growth Implementation In Utah, J. Ivy Harvey Thomson Aug 2020

Evaluation Of Best Practices For Urban Water Conservation And Water-Smart Growth Implementation In Utah, J. Ivy Harvey Thomson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Policies and programs have been utilized throughout the United States (U.S.) to reduce water use as a strategy to ensure sufficient water supplies for future demand. As governmental leaders and policy makers face increasing freshwater scarcity and supply unpredictability, along with rising costs and decreased federal funding, Best Practices (BPs) in water conservation are increasingly important to facilitate decision-making in choosing which strategies to employ. This project uses policy analysis to review and summarize various BPs, referencing both academic and professional literature. National fixture efficiency standards enacted in 1992 are credited as among the leading factors reducing indoor water use …


Wildfire In The West: An Initial Analysis Of Wildfire Impacts On Hydrology And Riverbed Grain Size In Relation To Salmonid Habitat, Natalie J. Gillard Dec 2019

Wildfire In The West: An Initial Analysis Of Wildfire Impacts On Hydrology And Riverbed Grain Size In Relation To Salmonid Habitat, Natalie J. Gillard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Historically wildfires have been beneficial to forests, however, human developments have encroached on forests when wildfire was artificially suppressed by federal and state agencies. The area burned by wildfire each year has increased twenty-fold in the past three decades. Large, high severity fires pose increased threats to human and aquatic communities within and downstream of the burned area due to post-wildfire effects on flooding and sedimentation. We need to understand the impacts of wildfires to be able to mitigate their damages and to recognize their potential benefits. This research addresses the questions: 1) Do wildfires impact rural and urban economies …


Evaluation Of Stream Bank Restoration To Improve Water Quality In A Semi-Arid Stream, Johnathan Neenan Dec 2019

Evaluation Of Stream Bank Restoration To Improve Water Quality In A Semi-Arid Stream, Johnathan Neenan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Human watershed activities such as converting land cover to agriculture and livestock grazing have negatively impacted stream water quality worldwide. One such case is Utah’s Upper Sevier River where a loss of woody bank vegetation (reduced shading) and accelerated bank erosion (increased fine sediment inputs) has led to increased stream temperature and water turbidity. As a result, the state of Utah sought to improve water quality conditions using streambank restoration. While commonly recommended and performed, the effectiveness of this sort of restoration has rarely been quantified. Here, I evaluated a restored reach of the Upper Sevier River near Hatch, UT …


An Examination Of What Motivates Utah Residents To Adopt The Practice Of Rainwater Harvesting, D. Wayne Honaker Dec 2018

An Examination Of What Motivates Utah Residents To Adopt The Practice Of Rainwater Harvesting, D. Wayne Honaker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although most of the earth is covered in water, a very limited amount of that water is fresh water, which is essential to our survival. Therefore, it is imperative that we do all that is possible to conserve and protect our extremely limited water resources, especially in arid regions such as the American West. While there are many ways and means to protecting and preserving our water resources, this thesis focuses on the strategy of rainwater harvesting (RWH) as it is done throughout the state of Utah. RWH is defined as taking the precipitation that falls on our built structures …


Stream Temperature Monitoring And Modeling To Inform Restoration: A Study Of Thermal Variability In The Western Us, Jessica R. Wood Dec 2017

Stream Temperature Monitoring And Modeling To Inform Restoration: A Study Of Thermal Variability In The Western Us, Jessica R. Wood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water temperature is an important variable for aquatic ecosystems. Salmonid population numbers and distribution are heavily influenced by stream temperature, and there is growing concern about the health of salmonid populations with anticipated climate change. Managers are looking to efficiently evaluate options to maintain stream temperatures needed by salmonids. This study evaluated and compared stream temperature restoration alternatives in two streams with warm temperatures using stream temperature monitoring and modeling.

The first study identified pockets of cold water that are important to native fish species in Nevada’s Walker River. Comparison of monitoring results with existing basin-scale model outputs identified two …


Longitudinal Thermal And Solute Dynamics In Regulated Rivers, Muhammad Rezaul Haider Dec 2017

Longitudinal Thermal And Solute Dynamics In Regulated Rivers, Muhammad Rezaul Haider

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dam releases increase river stage and can reverse groundwater movement into and out of the river. As the flood, thermal, and solute waves travel downstream in a regulated river, the size of the waves is anticipated to be affected both by river processes and exchanges with near river groundwater. This study established a modeling framework to quantify the influences of the groundwater exchanges on the temperatures and solute concentration dynamics along regulated rivers. The wave properties, volume of exchanges, conservative solute mass exchanges, and heat energy exchanges were calculated as a function of time and distance downstream. Results show that …


Optimizing Barrier Removal To Restore Connectivity In Utah’S Weber Basin, Maggi Kraft Dec 2017

Optimizing Barrier Removal To Restore Connectivity In Utah’S Weber Basin, Maggi Kraft

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

River barriers, such as dams, culverts and diversions are important for water conveyance, but disrupt river ecosystems and hydrologic processes. River barrier removal is increasingly used to restore and improve river habitat and connectivity. Most past barrier removal projects prioritized individual barriers using score-and-rank techniques, neglecting the spatial structure and cumulative change from multiple barrier removals. Similarly, most water demand models satisfy human water uses or, only prioritize aquatic habitat, failing to include both human and environmental water use benefits. In this study, a dual objective optimization model identified in-stream barriers that impede quality-weighted aquatic habitat connectivity for Bonneville cutthroat …


Twentieth Century Channel Change Of The Green River In Canyonlands National Park, Utah, Alexander E. Walker Dec 2017

Twentieth Century Channel Change Of The Green River In Canyonlands National Park, Utah, Alexander E. Walker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since the early 20th century, river channels of the Colorado River basin have narrowed, decreasing available riparian and aquatic habitat. Changes are considered to be the result of three major factors: wide-spread water development, increasing hydroclimate variability and the invasion of non-native tamarisk (Tamarix spp.), altering flow regime and sediment supply. Different studies have reached different conclusions about the relative roles of flow regime, sediment supply and tamarisk in causing narrowing.

I investigated channel change in the lower Green River within Canyonlands National Park to describe channel changes in the 20th century and understand the roles …


Changes In Floodplain Inundation Under Non-Stationary Hydrology For An Adjustable, Alluvial River Channel, Bruce C. Call May 2017

Changes In Floodplain Inundation Under Non-Stationary Hydrology For An Adjustable, Alluvial River Channel, Bruce C. Call

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Predicting the frequency and aerial extent of flooding in river valleys is essential for infrastructure design, environmental management, and risk assessment. Such flooding occurs when the discharge of water within a river channel exceeds its maximum capacity and the extra water submerges the adjoining floodplain surface. The maximum capacity of a channel is controlled by its geometry, gradient, and frictional resistance. Conventional flood prediction methods rely on assumptions of unchanging flood probabilities and channel capacities. However, changes in climate, land cover, and water management have been shown to systematically shift the magnitude and variability of flood flows in many systems. …


Are Experimentally Derived Estimates Of Thermal Tolerance Useful In Interpreting Species Distribution Models, Iva Sokolovska May 2014

Are Experimentally Derived Estimates Of Thermal Tolerance Useful In Interpreting Species Distribution Models, Iva Sokolovska

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Species distribution models are frequently used in ecology to predict the spatial and temporal occurrence of organisms. Direct interpretation of these models assumes that the relationships between the organisms and their environment are manifestations of causal mechanisms. However, in general, the mechanisms producing these associations have not been experimentally validated, which questions our confidence in their interpretation and application. Temperature is one of the most important factors influencing the fitness and distribution of aquatic organisms, and studying the thermal physiology of aquatic invertebrates could provide a useful approach for validating predictions of the species distribution models.

Experimental thermal tolerance studies, …


Factors Influencing The Distribution Of Brown Trout (Salmo Trutta) In A Mountain Stream: Implications For Brown Trout Invasion Success, Christy Meredith May 2012

Factors Influencing The Distribution Of Brown Trout (Salmo Trutta) In A Mountain Stream: Implications For Brown Trout Invasion Success, Christy Meredith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Brown trout (Salmo trutta), one of the world’s most successful introduced species in river and lake systems, negatively impacts native species through predation, competition, and systemwide effects. Thus, there is a need to understand factors controlling the distribution of brown trout, in order to prioritize and develop conservation and management strategies. Within the context of invasion success, I investigated how the physical characteristics of the Logan River influence the distribution of brown trout, as well as the potential for brown trout predation on a native fish, the mottled sculpin (Cottus bairdi).

In chapter 1, I evaluated …


The Influence Of Geology And Other Environmental Factors On Stream Water Chemistry And Benthic Invertebrate Assemblages, John R. Olson May 2012

The Influence Of Geology And Other Environmental Factors On Stream Water Chemistry And Benthic Invertebrate Assemblages, John R. Olson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Determining if a stream has been degraded by human activities requires knowing what that stream’s natural water quality and freshwater species composition would likely be without any alteration. However stream natural conditions vary greatly from stream to stream, making predicting natural conditions difficult. To determine natural stream conditions, I developed models to predict natural stream water chemistry at individual streams across the western USA. Specifically, the models predict a stream’s electrical conductivity (a measure of the amount of solids dissolved in water), acid neutralization capacity, and concentrations of calcium, magnesium, sulfate, total phosphorus, and total nitrogen. These models predict chemistry …


Environmental Assessment Of Streams: Linking Land Use, Instream Stressors, And Biological Indices To Infer Likely Causes Of Ecological Impairment, Jacob J. Vander Laan May 2012

Environmental Assessment Of Streams: Linking Land Use, Instream Stressors, And Biological Indices To Infer Likely Causes Of Ecological Impairment, Jacob J. Vander Laan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To protect and restore stream biota, managers need to be able to both detect biological degradation and infer likely causes of impairment. Managers commonly develop indices based on stream biota to assess the biological condition of streams. However, the performance of these indices dictates the ability to detect degradation, and although index performance varies widely, the sources of this variation are often unclear. In addition, bioassessments do not identify causes of impairment. My thesis research had two general goals: 1) develop indices to measure biological condition in Nevada streams and 2) quantify relationships between land uses, stressors, and biological condition …


The Transfer Of Agricultural Water To Municipal And Industrial Usages, Dallin Paul Stephens May 2011

The Transfer Of Agricultural Water To Municipal And Industrial Usages, Dallin Paul Stephens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The water that is available for beneficial use in Utah is quickly approaching full appropriation; water that has been claimed is nearing the amount that is available for use. The Division of Water Resources of the State of Utah has organized a three-part plan to "Plan, Conserve, Develop and Protect Utah's Water Resources." One of these three elements has a focus to "provide comprehensive water planning." Such planning is best achieved when current and accurate data on the uses of the state's water are available.

The primary purpose of this thesis was to provide an evaluation, from data collected on …


Piano Key Weir Head Discharge Relationships, Ricky M. Anderson May 2011

Piano Key Weir Head Discharge Relationships, Ricky M. Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A piano key (PK) weir is a type of nonlinear (labyrinth-type) weir developed specifically for free-surface flow control structures with relatively small spillway footprints. Currently, no generally accepted standard PK weir design procedure is available. This is due, in part, to the large number of geometric parameters and a limited understanding of their effects on discharge efficiency (discharge efficiency is quantified by the discharge coefficient of the standard weir equation). However, Hydrocoop, a non-profit French dam spillways association, has recommended a PK weir design and a head-discharge relationship specific to that geometry.

To develop a better understanding of the effects …


Residential Landscape Water Check Programs: Exploring A Conservation Tool, Diana T. Glenn Dec 2010

Residential Landscape Water Check Programs: Exploring A Conservation Tool, Diana T. Glenn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In response to drought and regional growth in the arid western United States, urban water demand management is increasingly important. Single family residences use approximately 60% of their water consumption to irrigate landscapes often in excess of plant water requirements. This study utilized a quasi-experimental design to investigate outdoor water consumption and assess the effectiveness of a landscape water check conservation program. Study objectives included describing a contextualized landscape system to reveal variables influencing water use, identifying better ways to evaluate landscape water use, and more effectively targeting and delivering water conservation programs.

The study was conducted during the 2004 …


Assessing Linkages Among Landscape Characteristics, Stream Habitat, And Macroinvertebrate Communities In The Idaho Batholith Ecoregion, Andrew C. Hill Dec 2010

Assessing Linkages Among Landscape Characteristics, Stream Habitat, And Macroinvertebrate Communities In The Idaho Batholith Ecoregion, Andrew C. Hill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the composition of lotic communities and the landscape processes and habitat characteristics that shape them is one of the main challenges confronting stream ecologists. In order to better understand the linkages among landscape processes, stream habitat, and biological communities and to understand how accurately our measurements represent important factors influencing biological communities, it is important to test explicit hypotheses regarding these linkages. Increasing our understanding of aquatic communities in a hierarchical context and recognizing how well our measurements represent factors structuring aquatic communities will help managers better evaluate the influence of land management practices on aquatic ecosystems, direct conservation …


Pervasive Thermal Consequences Of Stream-Lake Interactions In Small Rocky Mountain Watersheds, Usa, Jessica D. Garrett Dec 2010

Pervasive Thermal Consequences Of Stream-Lake Interactions In Small Rocky Mountain Watersheds, Usa, Jessica D. Garrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Limnologists and stream ecologists acknowledge the fundamental importance of temperature for regulating many ecological, biological, chemical, and physical processes. I investigated how water temperatures were affected by hydrologic linkages between streams and lakes at various positions along surface water networks throughout several headwater basins in the Sawtooth and White Cloud Mountains of Idaho (USA). Temperatures of streams and lakes were measured for up to 27 months in seven 6 – 41 km2 watersheds, with a range of lake influence. When they were ice-free, warming in lakes resulted in dramatically warmer temperatures at lake outflows compared to inflow streams (midsummer …